In The Presence Of My Enemies, by Gracia Burnham. Martin and Gracia Burnham were missionaries in the Philippines from 1986 to 2001, when they were kidnapped by the Abu Sayyaf, an Islamic extremist group. This is the account of the year of the captivity, along with many other kidnapped Filipinos. The "adventure" unfortunately ended with Martin being shot to death, so Gracia had to write the book alone.
I just started this book, and the first think I notice is that Ms. Burnham is in no way a writer. The writing style is very immature, but I can accept that. She was a missionary, not a novelist. The story does look like it will be an interesting one, as I see the various kidnappees and how they survive in the jungle with their kidnappers.